6,744 research outputs found
Transport anomalies in a simplified model for a heavy electron quantum critical point
We discuss the transport anomalies associated with the development of heavy
electrons out of a neutral spin fluid using the large-N treatment of the
Kondo-Heisenberg lattice model. At the phase transition in this model the spin
excitations suddenly acquire charge. The Higgs process by which this takes
place causes the constraint gauge field to loosely ``lock'' together with the
external, electromagnetic gauge field. From this perspective, the heavy fermion
phase is a Meissner phase in which the field representing the difference
between the electromagnetic and constraint gauge field, is excluded from the
material. We show that at the transition into the heavy fermion phase, both the
linear and the Hall conductivity jump together. However, the Drude weight of
the heavy electron fluid does not jump at the quantum critical point, but
instead grows linearly with the distance from the quantum critical point,
forming a kind of ``gossamer'' Fermi-liquid.Comment: 15 pages, 3 figures. Small change in references in v
Cluster algebras of type
In this paper we study cluster algebras \myAA of type . We solve
the recurrence relations among the cluster variables (which form a T--system of
type ). We solve the recurrence relations among the coefficients of
\myAA (which form a Y--system of type ). In \myAA there is a
natural notion of positivity. We find linear bases \BB of \myAA such that
positive linear combinations of elements of \BB coincide with the cone of
positive elements. We call these bases \emph{atomic bases} of \myAA. These
are the analogue of the "canonical bases" found by Sherman and Zelevinsky in
type . Every atomic basis consists of cluster monomials together
with extra elements. We provide explicit expressions for the elements of such
bases in every cluster. We prove that the elements of \BB are parameterized
by \ZZ^3 via their --vectors in every cluster. We prove that the
denominator vector map in every acyclic seed of \myAA restricts to a
bijection between \BB and \ZZ^3. In particular this gives an explicit
algorithm to determine the "virtual" canonical decomposition of every element
of the root lattice of type . We find explicit recurrence relations
to express every element of \myAA as linear combinations of elements of
\BB.Comment: Latex, 40 pages; Published online in Algebras and Representation
Theory, springer, 201
Collaborative innovation: Catalyst for a destination’s event success
Purpose: This paper aims to contribute to theory concerning collaborative innovation through stakeholder engagement with reference to Glasgow City Marketing Bureau’s (GCMB’s) management strategies, which represent UK best practice in events procurement, leveraging and destination branding. Design/methodology/approach: The research adopts a case study design to facilitate an in-depth evaluation of the destination marketing organisation’s (DMO’s) critical success factors. Multiple perspectives on GCMB’s collaborative innovation are achieved through semi-structured interviews with senior managers from the bureau, key stakeholders and other DMOs. Findings: GCMB’s success results from long-term, extensive, collaborative engagement, a unique institutional structure and sustained political and financial support through to transformational leadership, strategic event selection and targeted marketing through “earned” distribution channels. Research limitations/implications: The study takes a single case study approach and focusses on GCMB’s event-led branding strategy. Given the importance but relative neglect of long-term inter-personal relationships in collaborative innovation, future research should focus on the development of social capital and adopt a longitudinal perspective. Practical implications: The paper provides insights into the collaborative innovation process with a range of stakeholders, which underpins GCMB’s events strategy and its leveraging of the city brand. In particular, the study highlights the need for entrepreneurial leadership and the development of long-term relationships for effective engagement with stakeholders. Originality/value: Previous research has focussed on outcomes and neglected pre-requisites and the process of collaborative innovation between destination stakeholders. This study examines this issue from the perspective of a successful DMO and presents a conceptual framework and new engagement dimensions that address this gap in knowledg
The shallow depth emplacement of mafic intrusions on a magma-poor rifted margin : An example from the Bight Basin, Southern Australia
This work comprises a part of the Great Australian Bight Deepwater Marine Program (GABDMP) for funding this project. The GABDMP is a CSIRO research program, sponsored by Chevron Australia the results of which will be made publically available. 3D seismic data was gratefully provided by TGS. Dougal Jerram and Craig Magee are thanked for constructive reviews; Adam Bumby is thanked for editorial handling.Peer reviewedPostprin
Three-Dimensional Seismic Imaging of Ancient Submarine Lava Flows : An Example From the Southern Australian Margin
This work comprises a part of the Great Australian Bight Deepwater Marine Program (GABDMP) for funding this project. The GABDMP is a CSIRO research program, sponsored by Chevron Australia the results of which will be made publicly available. 3D seismic data was gratefully provided by TGS. IHS are thanked for access to seismic interpretation software. Spectral decomposition was carried out using Foster-Findlay Associates Geoteric Software. Sverre Planke and Tracy Gregg are thanked for constructive reviews.Peer reviewedPublisher PD
Coleridge, Sara
An encylopaedia article on the life and writings of Sara Coleridge (1802-1852), for an online work of reference and scholarshi
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